What is ADSL?

Asymmetric digital subscriber line (ADSL) is a digital communication technology standard that enables telephone lines to send and receive data (as well as analog information).

Unlike a dial-up (analog) modem, an ADSL connection is continuous ("always-on"). The connection is ‘asymmetric’ in that more of the channel is allocated to receiving data (downloading) than sending (uploading). This reflects the usage patterns of typical subscribers; with more time spent browsing than maintaining websites.

The downstream speed of an ADSL connection starts at 512 Kbps (10x faster than standard dial-up speed of 51.2 Kbps) and ranges up to 6Mbps (6,000 Kbps) with download performance tending to the lower speed.

Related terms: bandwidth, download/upload